This invention relates to water inlets in a marine propulsion gear case for supplying cooling water to the water pump for cooling the engine.
Conventional gear case water inlets are provided by holes in the gear case through which water is supplied to the water pump. In some applications, conventional water inlets are not capable of supplying sufficient pressure and water flow. Insufficient pressure and flow may be caused by frothy or aerated water, typically due to obstructions on the bottom of the boat or to a high mounting of the engine on the transom, resulting in ventilation from the surface.
The present invention provides a water intake designed to provide an increased flow of water to the water pump. The water intake in accordance with the invention provides positive water pressure and increased flow to the water pump, while having little effect on boat speed due to increased drag. The water intake of the invention protrudes from the gear case and has an opening spaced outwardly therefrom adapted to receive water. The opening forces the water into the conventional gear case holes and to the water pump. The water intake of the invention is particularly well suited for mounting on a gear case having conventional cast-in water inlet holes.
Because of the increased water flow provided by the invention, the motor can be mounted higher on the transom than normal and still be supplied with a sufficient amount of cooling water. The raising of the motor is desirable because it enables increased boat speed.